Antennas for use in broad-ranging communication systems, such as cellular communications systems, are mounted on towers. Two types of towers for mounting antennas include lattice-type towers and monopole towers. Lattice-type towers comprise a plurality of poles arranged into lattice sections which are stacked one on top of the other to obtain the desired height. Monopole towers comprise a tubular mast.
Typically, a plurality of antennas, some transmitting antennas and some receiving antennas, are mounted on a single tower. It is desirable to be able to change the height and orientation of the antennas from time to time. This is easily accomplished on a lattice-type tower, because the antennas are mounted on removable brackets which can be relocated anywhere on the tower. Monopole towers are more limited in this regard. Antennas are typically mounted to a nonremovable platform at the top of a monopole tower. To lower the antennas on a monopole, one must replace the entire pole with a shorter one.
Accordingly, there is a need for an antenna mounting platform for a monopole tower which can be mounted at selectable positions along the length of the monopole.